Rafter beekeeping with Apis dorsata: some factors affecting the occupation of rafters by bees
Nguyen Quang Tani; Phung Huu Chinh; Pham Hong Thai; Vincent Mulder
The giant honey bee, Apis darsata, builds its single comb nest in the open. The colonies are defensive and demonstrate seasonal migration. Therefore, the domestication of this species in the way that the cavity nesting honey bees A. mellifera and A. cerana have been domesticated, has been thought to be impossible. However, in some Melaleuca forest areas of Vietnam, beekeepers use a traditional method to attract A. dorsata colonies that arrive in the area to build their nest on rafters, which have been raised before the Melaleuca trees start to bloom. This technique allows beekeepers to harvest honey two or three times from the same colony per season without destroying the bees and bee combs. Not all rafters become occupied by colonies. An experienced beekeeper may succeed in having 60% of his rafters occupied by bees but occupation may be much lower. In order to find out which factors influence occupation by A. dorsata, 507 rafters (occupied and not occupied with bees) were examined in 1993 and 1994. Because of seasonal variations, data was recorded separately for dry and rainy seasons. The direction, diameter, slope ofthe rafter and size of the open space in front of the rafter were recorded. Percentage occupation was highest (84.9% and 91.7% in the dry and rainy seasons, respectively) for rafters with large (> 25 mdiameter space) open spaces in front of them. Percentage occupation increased significantly with diameter ofthe rafter in the dry season, and followed this trend, but was not significant, in the rainy season. The most successful angle of slope of the rafter from the horizontal was found to range between 27' and 33.9°. We found that beekeepers mainly faced their rafters in a direction between north-east and south-east, although direction did not seem to affect the percentage occupation by A. dorsata.